openharmony-linux-demo-dashboard.conf: Allow local.conf TCLIBC overrides

The soft assigment needs to go before including openharmony-linux.conf
as that also defines a default (soft) for TCLIBC.

Signed-off-by: Andrei Gherzan <andrei.gherzan@huawei.com>

meta-ohos-demo/conf/distro/openharmony-linux-demo-dashboard.conf

 # Distro configuration for the dashboard demo
 
+# Epiphany fails with musl
+# https://bugzilla.yoctoproject.org/show_bug.cgi?id=14281
+TCLIBC ?= "glibc"
+
 require conf/distro/openharmony-linux.conf
 include conf/distro/include/ha-versions.inc
 
@@ -14,10 +18,6 @@ hostname_base-files_stm32mp1-av96 = "demo-dashboard-gateway"
 ST_VENDORFS = "0"
 ST_USERFS = "0"
 
-# Epiphany fails with musl
-# https://bugzilla.yoctoproject.org/show_bug.cgi?id=14281
-TCLIBC = "glibc"
-
 # Dynamic weston.ini configuration
 WESTON_DYNAMIC_INI = "1"
 WESTON_INI_NO_TOOLBAR = "1"